Until recently, fusible elements were generally stamped or otherwise formed from a single piece of sheet metal. Recent escalation in the price of precious metals, notably silver, has caused there to be a reduction in the use of such metals for fusible elements.
In order to retain the performance heretofore provided by one piece silver elements, composite fusible elements have evolved using copper and other less precious metals which closely parallel the performance heretofore derived from silver.
Composite fusible elements generally have relatively rigid tab components interconnected by a relatively fragile fusible component by means of a weld. In order to protect the fragile fusible component in such composites, the weld joint between components has been designed to additionally function as a hinge to absorb stresses which might ordinarily damage the fragile fusible component.